EP0352162A1 - Quick-change system for clamping jaws on a machine tool - Google Patents

Abstract

Inter alia quick change system, clamping jaw on a machine tool which includes self-locking locking means of a jaw (M₁) for clamping from the inside of a workpiece or a jaw (M₂) for clamping from the outside of a part. The jaw holder (P) is provided with at least two support parts (1₂₁, 1₂₂) for said jaws (M₁, M₂), the support faces (1₂₁₁) and (1₂₂₁) being inclined at an angle ( α) and (γ) respectively. These faces (1₂₁₁) and (1₂₂₁) cooperate, in the locked position, with bearing faces (M₂₁, M₂₂) corresponding to the jaws (M₁, M₂). One of the ends (2₁₀) of an assembly (2) has a face (2₁₀₀) inclined by an angle (β), while another face (2₁₀₁) is inclined by an angle (δ). These faces (2₁₀₀) and (2₁₀₁) cooperate in the locking position with the corresponding bearing face (M₂₃) or (M₂₄) respectively of one of the jaws (M₂) or (M₁).

Description

The present invention relates to a quick change system for clamping jaws on a machine tool, which can be used both for clamping inside or outside of the workpiece to be used for repetitive machining and successive from the outside or the inside of the rooms.

In its patent of invention No. 85 10958 of July 17, 1985, the applicant has described a system for rapid change of clamping jaws on a machine tool comprising self-locking jaw locking means (M) on the holder. jaw (P), said means being essentially constituted by a blocking element (1) having a base (1₁) on a face (1₁₀) on which rests said jaw (M) in the blocking position, and a part (1₂) of support for the jaw (M), the support face (1₂₀) of said support part (1₂) being inclined at an angle (α) with a horizontal plane perpendicular to the vertical plane to said face (1₁₀) of said base (1₁) for cooperating in the locking position, with a corresponding bearing face (M₂₀) of the jaw (M) on the one hand, and, on the other hand, by at least one assembly (2) for the maintenance of said jaw in the locking position, one of the ends (2₁₀) of a movable member (2₁) of said assembly (2) having at least one face (2₁₀ ) inclined at an angle (β) with a horizontal plane perpendicular to the vertical plane to said face (1₁₀) of said base (1₁) to cooperate, in the locked position, with a corresponding bearing face (M₂₀) of the jaw ( M), said angles (α) and (β) being overts in the same direction, said angle (α) being greater than said angle (β); said assembly (2) further comprising means (2₁, 2₂) allowing the unlocking and unlocking of said jaw (M). (See Fig. 1).

Said angle (α) is 1.4 to 2 times the angle (β) and the difference between the angles (α) - (β) is of the order of 7 ° to 10 °. [α = 1.4 ÷ 2 β; α -β: 7 ° ÷ 10 °].

The magnitude of the angle (α) is preferably 15 ° to 30 °, and that of the angle (β) is preferably 7 ° and 20 °.

The device described in this patent does not allow the use of jaws for clamping from the outside and / or from the inside of the workpiece, thus requiring the change of the jaw holder and / or the jaws for each mode. machining. This results in a considerable loss of time, a complication due to the multiplicity of the jaw holder and jaws required, and a relatively high production cost.

The object of the present invention is to overcome these drawbacks.

According to the present invention, the quick change system of, interalia, clamping jaws on a machine tool is characterized in that it comprises self-locking locking means of a jaw (M₁) for clamping from the inside. of a part or a jaw (M₂) for clamping from the outside of a part on a jaw holder (P), these means being essentially constituted by a blocking element having a base on a face on which rests said jaw (M₁, M₂) in the locked position, and at least two support parts for said jaws (M₁, M₂), the support faces being inclined at an angle (α) and (γ) respectively with horizontal planes (H₁, H₂) perpendicular to the vertical plane to said face of said base to cooperate in the locked position, with corresponding bearing faces of the jaws (M₁, M₂) on the one hand and on the other hand by minus one assembly for maintaining one of said jaws (M₁) or (M₂) in blocking position ge, one of the ends having a face inclined by an angle (β) with a horizontal plane (H₃) perpendicular to the vertical plane to said face of said base while another face is inclined by an angle (δ) with a horizontal plane (H₄), to cooperate in the locking position with the corresponding bearing face of one of the jaws (M₂) or (M₁) respectively, said angles (α, β, γ, δ) being open in the same direction, the angles (α, γ) being larger than the angles (β, δ); said assembly further comprising means permitting in a manner known per se the unlocking and unlocking of one of said jaws (M₁, M₂).

Said planes (H₁) and (H₂) are at a distance (R₁) and (R₂) respectively relative to a horizontal plane passing through the axis A - A of the mandrel, (R₁) being greater than (R₂), the plane (H₁) being located at a distance (a) from a horizontal plane passing through the axis x - x of the assembly (2) for holding a jaw (M₁, M₂) in the locked position while the plane (H₂) is at a distance (b) from the plane passing through the axis x - x.

Said plane (H₃) is at a distance (r₁) from the horizontal plane passing through the axis A - A, and that said plane (H₄) is at a distance (r₂) from said plane passing through the axis A - A, ( r₁) being greater than (r₂); said planes (H₃) and (H₄) being at a distance (c) and (d) respectively from said horizontal plane passing through the axis x - x.
The distance (a) can be equal to (b).
The distance (c) can be equal to (d).
The angle (α) can be equal to the angle (γ).
The angle (β) can be equal to the angle (δ).

Finally, each jaw (M₁, M₂) comprises a talan which, when blocking and locking one of said jaws (M₁, M₂) is housed in a corresponding recess in the peripheral part of said base of said element jaw holder.

Other advantages and characteristics will emerge from the following text and the figures relating thereto, given by way of example only.

• La figure 1 montre, en coupe, un système tel que décrit dans le brevet français N° 85 10958 au nom de la demanderesse.
• La figure 2a montre, en coupe, un système conforme à l'inven­tion pour le serrage par l'intérieur d'une pièce.
• La figure 2b montre, en coupe, un système conforme à l'inven­tion pour le serrage par l'extérieur d'une pièce.
• La figure 2c montre une coupe transversale passant par l'axe x - x de l'ensemble (2) du système conforme à l'invention.
• La figure 3 montre, en perspective, un porte-mors du système conforme à l'invention.
• Les figures 4a, 4b, 4c montrent, en perspective, des mors pour le serrage des pièces par l'intérieur, par l'extérieur et un mors ébauché.

The text and the figures relate to a mandrel as used on machine tools where, in general, the workpiece and / or the tool are impregnated with a rotary movement. It is however in the context of the invention to use this quick change system of a removable member on a fixed member, such as a jaw on a jaw holder, for clamping the most diverse parts, for example on a planer, shaping, mounting installations, etc., after having made the necessary modifications to adapt the system according to the invention to the desired use.

• Figure 1 shows, in section, a system as described in French patent No. 85 10958 in the name of the applicant.
• Figure 2a shows, in section, a system according to the invention for clamping from the inside of a part.
• Figure 2b shows, in section, a system according to the invention for clamping from the outside of a part.
• Figure 2c shows a cross section through the axis x - x of the assembly (2) of the system according to the invention.
• Figure 3 shows, in perspective, a jaw holder of the system according to the invention.
• Figures 4a, 4b, 4c show, in perspective, jaws for clamping the parts from the inside, from the outside and a roughed jaw.

The principle of blocking and locking of the jaws (self-locking) on the jaw holder is substantially identical to that described in the aforementioned French patent No. 85 10 958, allowing very high repetition of the operation, with great precision in the mounting of the jaws on the post-jaw and very little wear of the members forming part of the rapid exchange system.

As shown in Figures 2a, 2b, 2c and 3, the jaw holder (P) is made so that it can be used for jaws (M₁) for clamping from the inside of a part (not shown) in the drawings) or for jaws (M₂) for clamping from the outside of a part.

Indeed, the jaw holder (P) comprises a blocking element (1), an assembly (2) for holding the jaws (M₁ or M₂) in the blocking and locking position, a toothed zone (3), for example on the underside of the element (1) for holding the jaw holder (P) in position on the mandrel (not shown in the drawings) whose main axis is A - A. The jaw holder (P) is fixed to the mandrel by screws (4₁, 4₂) or the like.

The element (1) comprises a base (1₁) and support parts (1₂₁) and (1₂₂) for the jaw (M₁) and the jaw (M₂) respectively. These support parts are delimited on the side of the jaw (M₁) by a support face (1₂₂₁) inclined at an angle (γ) with a horizontal plane perpendicular (H₂) to the vertical plane to the face (1₁₀) of said base (1₁); and on the side of the jaw (M₂) by a bearing face (1₂₁₁) inclined at an angle (α) with a horizontal plane (H₁) to said vertical plane (1₁₀).

The assembly (2) essentially comprises a cylindrical jacket in which can move under the action of a spring (2₂), along the axis x - x, a pusher (2₁) having a substantially conical front end (2₁₀) or having two planes inclined by an angle (β) and (δ) respectively. A groove (2₅) can be provided in the pusher (2₁) in order to be able to maintain it in the locking and locking position or in the unlocking and unlocking position by means of a finger (2₆) screwed into the fixed element (1 ). As already mentioned above, a (upper) part of said head (2₁₀) has an inclined face (2₁₀₀) of an angle (β) with a horizontal plane (H₃) perpendicular to the vertical plane to said face (1₁₀ ), and a part (lower) of said head (2₁₀) has an inclined face (2₁₀₁) of an angle (δ) with a horizontal plane (H₄).

Each jaw (M₁) and (M₂) has at one of its ends an inclined face (M₂₁) and (M₂₂) respectively; the angle of inclination of the face (M₂₂) is equal to the angle of inclination (γ) of the face (1₂₂₁) of the element (1), and the angle of inclination of the face (M₂₁ ) is equal to the angle (α) of the face (1₂₁₁) of the element (1). In the jaw locking position (M₁) on the jaw holder (P), the inclined face (M₂₂) of the jaw (M₁) cooperates with the inclined face (1₂₂₁) of the jaw holder (P); similarly, in the jaw locking position (M₂) on the jaw holder (P), the inclined face (M₂₁) of the jaw (M₂) cooperates with the inclined face (1₂₁₁) of the jaw holder (P). The other end of each jaw (M₁) and (M₂) has a heel (M₄₀₁) and (M₄₀₂) respectively which is housed, in the locked position, in one of the recesses (1₁₁) and (1₁₂) respectively; these recesses are formed diametrically opposite in the periphery of the base (1₁) of the element (1). It is thus possible to mount on the jaw holder (P) either at least one jaw (M₁) for clamping from the inside, or at least one jaw (M₂) for clamping from the outside of a workpiece to machine, for example. To block and lock the jaws (M₁), in the locked position, an inclined face (M₂₂) of the jaw (M₁) cooperates with the inclined face (1₂₂₁) of the jaw holder (P), the angle of inclination (γ) of the faces (M₂₂) and (1₂₂₁) being identical. Similarly, in the jaw locking position (M₂), its inclined face (M₂₁) cooperates with the inclined face (1₂₁₁) of the jaw holder (P), the angle of inclination (α) of the faces (M₂₂) and (1₂₁₁) being identical.

The horizontal planes (H₁, H₂, H₃, H₄) are at distances (R₁, R₂, r₁ and r₂) from a horizontal plane passing through the longitudinal axis A - A of the mandrel: R₁> r₁> r₂> R₂ . The planes (H₁ and H₂) are at distances (a) and (b) respectively from a horizontal plane passing through the axis x - x, and the planes (H₃ and H₄) at distances (c) and ( d) respectively of this same horizontal plane passing through the axis x - x. The distance (a - c) is therefore equal to (R₁ - r₁). The angle (α) is always greater than the angle (β), and the angle (γ) is always greater than the angle (δ).

It is therefore possible, that by modifying, as required, at least one of the distances (R₁, r₁, r₂ and R₂) to constitute a range of jaws for clamping a part from the inside or by l 'outside. In particular, for (a = b) and (c = d), the angle (α) is equal to the angle (γ) and the angle (β) is equal to the angle (δ); this allows the use of the same jaw for clamping from the inside and / or the outside of a part.

Many modifications and / or improvements can be made to the systems described above without departing from the scope of the invention.

Claims (8)

1.) - Quick change system of, interalia, clamping jaws on a machine tool, characterized in that it comprises self-locking locking means of a jaw (M₁) for clamping from the inside of a piece or a jaw (M₂) for clamping from the outside of a piece on a jaw holder (P), these means being essentially constituted by a blocking element (1) having a base (1₁) on one face (1₁₀) on which said jaw (M₁, M₂) rests in the locked position, and at least two support parts (1₂₁, 1₂₂) for said jaws (M₁, M₂), the support faces (1₂₁₁) and ( 1₂₂₁) being inclined at an angle (α) and (γ) respectively with horizontal planes (H₁, H₂) perpendicular to the vertical plane to said face (1₁₀) of said base (1₁) to cooperate in the locking position, with corresponding bearing faces (M₂₁, M₂₂) of the jaws (M₁, M₂) on the one hand and on the other hand by at least one assembly (2) for May holding one of said jaws (M₁) or (M₂) in the locked position, one of the ends (2₁₀) having a face (2₁₀₀) inclined at an angle (β) with a horizontal plane (H₃) perpendicular to the plane vertical to said face (1₁₀) of said base (1₁) while another face (2₁₀₁) is inclined at an angle (δ) with a horizontal plane (H₄), to cooperate in the locked position with the face of corresponding support (M₂₃) or (M₂₄) respectively of one of the jaws (M₁) or (M₂), said angles (α, β, γ, δ) being open in the same direction, the angles (α, γ) being more larger than the angles (β, δ); said assembly (2) further comprising means (2₁, 2₂) allowing, in a manner known per se, the unlocking and unlocking of one of said jaws (M₁, M₂). 2.) - System according to claim 1, characterized in that said planes (H₁) and (H₂) are at a distance (R₁) and R₂) respectively relative to a horizontal plane passing through the axis A - A of mandrel, (R₁) being larger than (R₂), the plane (H₁) being located at a distance (a) from a horizontal plane passing through the axis x - x of the assembly (2) for holding a jaw (M₁, M₂) in the locked position while the plane (H₂) is at a distance (b) from the plane passing through the axis x - x. 3.) - System according to claim 1 or claim 2, characterized in that said plane (H₃) is at a distance (r₁) from the horizontal plane passing through the axis A - A, and that said plane (H₄) is at a distance (r₂) from said plane passing through the axis A - A, (r₁) being greater than (r₂); said planes (H₃) and (H₄) being at a distance (c) and (d) respectively from said horizontal plane passing through the axis x - x. 4.) - System according to one of the preceding claims, characterized in that (a) is equal to (b). 5.) - System according to claim 3 or claim 4, characterized in that (c) is equal to (d). 6.) - System according to one of the preceding claims, characterized in that the angle (α) is equal to the angle (γ). 7.) - System according to one of the preceding claims, characterized in that the angle (β) is equal to the angle (δ). 8.) - System according to one of the preceding claims, characterized in that each jaw (M₁, M₂) comprises a heel (M₄₀₁, M₄₀₂) which, when blocking and locking one of said jaws (M₁, M₂) is housed in a corresponding recess (1₁₁, 1₁₂) in the peripheral part of said base (1₁) of said element (1) of the jaw holder.

Images